Titanium battery compartment with a copper head. Compartmentalized tube could serve as reverse polarity protection and help isolate the lithium cells from the heat while the copper head would tranfer heat outward much more effectively than a ti alloy. Deep thin (but not too thin to resist bending) fins on the head to maximize surface area. Side switch with lighted battery state indicator and tail lockout. Programmable driver with user-selectable number of modes and ramping set levels for modes. Second switch for temporary turbo mode and signalling. Main and secondary side switches. When on depressing second switch puts light in turbo mode as long as it is held and when released returns to previous level. When off second switch illuminates to ramp set level as long as held for signalling.

Or, for setting modes, user would enter programming mode, and after a flash quickly press the button to set the number of modes. Light flashes twice. Press button once. Light flashes. User presses button once, waits one second, then presses button six times to set first mode to 5%. Light flashes. User presses button twice for mode 2. Light flashes. User presses button three times, waits, and presses button six times setting second level to 25%. 1 press = 0.

Titanium battery compartment with a copper head. Compartmentalized tube could serve as reverse polarity protection and help isolate the lithium cells from the heat while the copper head would tranfer heat outward much more effectively than a ti alloy. Deep thin (but not too thin to resist bending) fins on the head to maximize surface area. Side switch with lighted battery state indicator and tail lockout. Programmable driver with user-selectable number of modes and ramping set levels for modes. Second switch for temporary turbo mode and signalling. Main and secondary side switches. When on depressing second switch puts light in turbo mode as long as it is held and when released returns to previous level. When off second switch illuminates to ramp set level as long as held for signalling.

do you prefer PWM or PFM? if it is PWM, what the frequency you require? thanks

Prefer constant current but pwm at frequencies above typical audio range would work (around 20k). Just giving some ideas I’d like to see implemented. Still need to put myself through a refresher course on circuit theory and design but if someone else could build a light with those fearures sooner I’d buy it.

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If you want to keep it affordable, an AA form factor is the best choice.
The problem with AA lights is more about the driver, which has to be efficient in boost mode for Ni-Mh and handle 14500 Li-ion voltage at the same time…

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